The present disclosure generally relates to implantable medical devices, and more particularly relates to implantable devices for controlled drug delivery to the bladder and other genitourinary sites.
Systems for delivering drug locally to the bladder are known. For example, instillation permits delivering a solution of drug locally to the bladder, but drawbacks are present, such as the inability to achieve continuous drug delivery over an extended period. Continuous drug delivery can be achieved from implantable devices, but many implantable devices are not suited for the bladder. For example, some implantable devices are excreted from the bladder under the forces of urination, frustrating drug delivery. Also, many implantable devices cannot fit through the urethra, preventing minimally invasive deployment through this natural pathway. Other devices may fit through the urethra in an unfilled state but must be loaded with the drug after implantation. Furthermore, many known implantable devices cannot achieve sustained and controlled delivery of a therapeutically effective amount of drug over an extended period. For example, some known devices that are small enough to be deployed through the urethra are too small to hold a sufficiently large drug payload.
A need therefore exists for implantable devices that can be deployed through a natural orifice and/or lumen of the body into a body cavity, such as through the urethra into the bladder, and can be retained in the body under expected conditions, such as within the bladder during urination. Preferably the devices provide controlled release of one or more drugs for an extended period following implantation.